Rail with rail-pressure sensor
In the rail, the compressed fuel is stored temporarily and distributed to the injectors.
The rail-pressure sensor measures the current fuel pressure in the rail.
| Item | Explanation |
|---|---|
| 1 | Electrical connection |
| 2 | Evaluating circuit |
| 3 | Membrane with sensor element |
| 4 | High-pressure connection |
The fuel pressure reaches the diaphragm with sensor element through the high-pressure connection. The deformation of the membrane is converted via the sensor element into an electrical signal. The evaluating circuit processes the signal and forwards an analogue voltage signal to the DME. The voltage signal rises in linear form with increasing fuel pressure.
The signal from the rail-pressure sensor is an important input signal of the DME for activation of the quantity control valve (component of the high pressure pump). If the rail-pressure sensor fails, the quantity control valve is activated in emergency operation by the DME.